This proposal describes an experimental approach to the identification, recording and reporting of physical and physiological disorders and of social problems in primary health care settings. The purpose of such an exercise, involving primary health care personnel in an international range of settings is the development of an acceptable and reliable tri-axial classification of health problems that could be used throughout the world. It is proposed to determine the extent to which such an approach to the classification of health problems could be incorporated into a system of routine data recording and reporting compatible with existing methods of classification and in particular with the proposed 10th edition of the International Classification of Diseases. The study aims to increase the liklihood that the social and psychological aspects of the burden of ill-health will be more accurately identified, assessed and recorded. In this way it will become possible to prepare primary health care workers to provide effective treatment to their patients, and to provide policy makers with the information that is needed for better planning of health services and for the correction of major environmental contributors to ill-health.